Hi, all I encounter this problem when I try to send NMI to guest. I don't know how. I think if I can access to the qemu-monitor, I can just do this command in the qemu-monitor: "nmi <cpu#>". But I don't know how to access to qemu-monitor, I think I can get help here. I noticed that the guest is started by libvirt with these parameters: -chardev socket,id=monitor,path=/var/lib/libvirt/qemu/vm~laijs.monitor,server,nowait \ -mon chardev=monitor,mode=control So I wrote a simple program and tried to access qemu-monitor by accessing the socket /var/lib/libvirt/qemu/vm~laijs.monitor. It failed, because I don't know how to send commands with "mode=control", I don't know the protocol for exchanging data with this file. (If I start guest with the same parameters as libvirt but using "mode=readline", I successfully sent commands to qemu-monitor by my simple program, I just send text commands) I noticed that libvirt 0.8.3 supports remote protocol and arbitrary qemu commands, but I did not found any document, how can I use it? Thanks, Lai, (I'm not in this email-list:libvir-list@redhat.com, please ensure my email address in your cc-list when you reply, thanks)